Field of Invention
The present invention relates to LED, and more specifically relates to a control circuit for LED and an active bleeder.
Description of the Related Art
The LED (Light-Emitting Diode) lamps are widely used in a variety of electronic applications due to LED lamps have significant advantages, such as long life time, small size, and high efficiency. In general, the LED system comprises a dimmer, such as TRIAC dimmer, which is used to adjust the brightness of the LED lamps. The TRIAC dimmer is triggered every half of AC cycle. While it is trigged, the current flowing through it should be kept higher than a threshold current for the remaining half AC cycle. The threshold current is called holding current. Thus, the present invention provides a control circuit for LED and an active bleeder for sinking a bleeding current in order to keep the current flowing through the dimmer higher than the holding current.